Unitary clamping and locking assembly for tie rods



Dec. 13, 1955 P. A. LEMMA 2,726,432

I UNITARY CLAMPING AND LOCKING ASSEMBLY FOR TIE RODS Filed Dec. 26. 1952 FIG. 1. A p 35 30 ll 22 If, 32 A\54 42 G0 INVENTOR I PETE/2 A. LEMMA ATTORN EY wam 1 1 United States Patent UNITARY CLAMPING AND LOCKING ASSEMBLY FOR TIE RODS Peter A. Lemma, North Bellmore, N. Y. Application December 26, 1952, Serial No. 328,002

12 Claims. (Cl. 25131) The present invention relates to the construction of concrete forms of the type including spaced Walls interconnected by tie rods, and particularly to a unitary clamping and locking assembly for detachably fixing the ends of tie rods to the walls of the form.

In assembling panels or walls for concrete forms, it is conventional to use tie rods or braces which extend between opposing walls or panels and are anchored therebetween for maintaining the walls or panels in fixed positions prescribing a predetermined area for the reception of a mass of concrete. When the poured concrete has sufiiciently set, the temporary supporting walls are removed and the tie rods or braces remain permanently embedded in the concrete wall. Among the requisites for the connection of the tie rods to the walls or panels are ease of attaching the respective tie rods to the walls, the sturdiness and strength of the attachment thus formed, and the ability to readily detach the tie rod from the walls or panels when the walls or panels are to be removed after setting of the concrete.

Accordingly, it is an object of the present invention to provide clamping and locking assemblies for securing tie rods to form walls or panels which embody one or more of the aforesaid desirable features.

Another object of the present invention is to provide a tie rod gripping and clamping mechanism which may be permanently fixed to the form walls and readily manipulated exteriorly thereof for effecting the securernent to and. detachment of tie rods from the form walls.

In addition to the problem of temporarily connecting the tie rods to form walls, it is necessary to comply with building regulations and codes. Building codes often require that the tie rods which are to be permanently embedded in the concrete, have their ends completely enclosed by the concrete mass. In some of the devices heretofore employed, the tie rods were greater in length than the width of the wall to be formed and provided with weakened portions facilitating the breaking off of end-adjacent pieces of the tie rods after the tie rods were embedded to avoid having the enlarged gripping ends of the tie rods project beyond the concrete wall. This was done to comply with the mentioned building codes, but necessarily resulted in loss in material since the broken-off portions of the tie rods were obviously of no utility and had to be discarded. This greatly increased costs without deriving additional structural strength, especially when considering the large number of tie rods employed in constructing foundations and the like. 1

Accordingly, it is a further object of the present invention to provide a clamping and locking assembly for detachably fixing a tie rod to form walls by means of which the ends of the tie rod are positioned tobe embeddedwithin the concrete wall thereby effectively decreasing the tie rod length and the cost thereof. In accordance with this aspect of the present invention, a maximum length of the tie rod is embedded within the concrete to take full advantage of the structural strength contributed by the tie rod to the concrete wall.

Many other objects, features and advantages of the present invention will be understood by those skilled in the art by reference to the description of a preferred embodiment in accordance with the present invention, the specific description pointing out the exact and complete manner in which I have made an advance in the arts and sciences. The description will be best understood by reference to the drawings, wherein:

Fig. l is a longitudinal view, with parts broken away and sectioned, showing a clamping and locking assembly embodying features of the present invention, arranged in the tie-rod releasing position subsequent to the setting of a concrete mass and with the form wall or panel spaced outwardly from the concrete mass;

Fig; 2 is a view similar to Fig. 1, but showing the clamping and locking assembly rigidly attached to the enlarged end of the tie rod with the form wall against the concrete mass subsequent to pouring;

Fig. 3 is a perspective view showing the novel gripper assembly of the present invention and the tightening wedge associated therewith, which in conjunction with the housing make up the clamp jaw and wedging arrangement of the present invention;

Fig. 4 is an elevational view of the clamping and locking assembly of Figs. 1 and 2 as shown between two adjacent form panels with the tightening wedge in a locking position; and,

Fig. 5 is a fragmentary sectional view taken along the line 55 of Fig. 4 and looking in the direction. of' the arrows.

Referring now specifically to the drawings, there is shown a clamping and locking assembly, generally designated'by the reference numeral 14 supported between a pair of adjacent form panels, A, B which cooperate to define all of or part of a form wall. Although only one assembly it) has been shown, it is to be expressly understood that duplicate assemblies are mounted between form panels and opposite panels A and B, an appropriate number of pairs of assemblies being provided in accordance with the contemplated form construction. For a better understanding of the arrangement of the respective form panels to obtain a particular form configuration, specific reference should be made to my co-pending application Ser. No. 328,001 filed concurrently herewith. For the present purposes, only one assembly need be illustrated, since the number and location of these assemblies will be determined by the form wall construction.

The assembly 1%) includes an elongated cylindrical housing 12 provided with a longitudinal bore 14 terminating in open ends l6, 18. The housing 12' is arranged within a concentric cutout 25) formed in the panels A, B. As best seen in Figs. 4 and 5, the cutout 20 for the housing is defined by two semicircular grooves provided in the abutting uprights a, b of the adjacent form panels A, B, the semi-circular grooves being in alignment with each other when the panels are locked in position in accordance with the teachings of the aforementioned copending application.

Fixed transversely of or formed integrally with the housing 12 adjacent the open end 16 is a pressure plate 22, which straddles both form panels, as seen in Fig. 4. Preferably, but not necessarily the pressure plate 22 may be fixed to one of the form panels, such as the panel A by appropriate screws or bolts, designated by the ref erence numeral 24. The pressure plate 22 is formed with a central opening 26 concentric with respect to the open end 16 of the housing 12 and forming a continuation of the internal bore 14 thereof.

The outer periphery of the housing 12 adjacent the open end 18 is formed with a threaded part '28- which receives and supports an enlarged head 30 arranged concentrically of the housing and seated within an appropriate seat or countersink 31 provided Within the form panel, the seat or countersink extending inwardly from the form faces a, b.

Both the enlarged head 30 and the adjacent part of the housing 12 are cut away to provide an internal conical bearing seat or cam surface 32 for a purpose to be subsequently described. It is to be noted that the housing 12 with the enlarged head 30 thereon project outwardly of the internal form faces a, b for a substantial distance.

Disposed within the housing 12 is a gripper assembly, generally designated by the numeral 32, which includes a substantially U-shaped common operator 34 having spaced legs 36, 38 interconnected by a curved bight 40. As seen best in Figs. 1 or 3, the legs or arms 36, 38 of the operator 34 gradually diverge from each other at locations progressively spaced from the bight 40, the latter providing an enlarged bearing seat 42. Secured to or formed integrally with the free ends of the legs 36, 38 of the operator 34 are the clamping or gripping jaws 44, 46 each of which is substantially in the form of a longitudinal half-section of a cone. The jaws 44, 46 include adjacent faces 48, 50 adapted to be brought into abutment with each other upon application of a lateral load to the gripping jaws. In this connection, the integral gripper assembly 32 is formed of a resilient material of a springiness sufficient to assure that the legs or arms 36, 38 normally assume the divergent position illustrated in Fig. l and are displaceable into the convergent position of Fig. 2 when a sufficient transverse loading force is applied. The abutment faces 48, 50 of the coacting gripping jaws 44, 46 are each provided with semi-circular coaxial cutouts 52, 54 substantially complementary to the shaft of the tie rod T, as seen in Fig. 2, the respective cutouts 52, 54 opening into dome-shaped cutouts 56, 58 appropriately dimensioned with respect to the head t' of the tie rod T. Accordingly, when the gripper assembly 32 is in the position of Fig. 2, wherein the coacting jaws 44, 46 surround the tie rod head t and the adjacent portion of the tie rod proper, there is no possibility of longitudinally displacing the gripper assembly 32 relative to the tie rod T.

In order to preclude displacement of the gripper assembly 32 from the locking position illustrated in Fig. 2, and to initially displace the assembly from the tie rod receiving and releasing position of Fig. 1, there is provided a tightening or looking wedge 60, which includes an abutment surface 62 adapted to bear against the pressure plate 22 when the wedge 60 is brought into the operative position, illustrated by the full lines of Fig. 5. Additionally, the wedge includes a wedging surface 64 appropriately inclined with respect to the abutment surface 62 and an integral lock finger 66 extending parallel to and spaced from the wedging surface 64 and cooperating therewith to define a guideway 65 for the curved bight 40 of the operator 34. Any suitable means may be employed for constricting the open end of the guideway 65 to preclude accidental removal of the lock wedge from the supporting bight. Normally the wedge 60 is arranged in the position illustrated in Fig. 1 in which the wedge extends in end-to-end alignment with the gripper assembly 32 and can be manually grasped and pulled backwardly until the conical cooperating jaws 44, 46 are nested within the conical seat 32. It is to be noted that the conical surfaces of the jaws 44, 46 and the conical seat 32 cooperate to cam the jaws 44, 46 from the separated position of Fig. 1 to the coacting position of Fig. 2, wherein the surfaces 48, 50 abut. In this latter position, the cutouts 52, 54 and 56, 58 cooperate to define a complementary bearing seat for the adjacent portions of the tie rod T. When the locking or tightening wedge 60 is pulled back sufficiently, it can be swiveled on the bearing seat 42 from the position of Fig. 1, illustrated also by the broken lines of Fig. 5, to the full line position of Figs. 2 and 5 wherein the abutment surface 62 lies against the pressure plate 24, the latter serving as a continuous, smooth and uninterrupted bearing surface for the wedge. Swinging of the Wedge can be readily accomplished due to the provision of the enlarged and curved seat 42 on the bight 40 of the gripper assembly 32. Thereupon, the wedge is locked by imparting a blow to the wedge in the appropriate direction, such as from right to left, in Fig. 5.

A typical application of the gripper and clamping assembly is as follows:

The assembly of Fig. l with the wedge 60 thereon is placed between form panels at appropriate locations, such as between adjacent form panels A, B on one wall and coplanar panels on an opposing wall. laws 44, 46 are brought into position with respect to the tie rod T and the wedge 66 is displaced until the bearing seat defined by the cutouts 52, 54, 56, 58 is engaged about the tie rod head t' in the adjacent end of the tie rod T. Thereupon, the wedge is pivoted from the unlocked position U until the bearing surface 62 lies against the pressure plate 22, whereupon a blow is imparted to the wedge 62 to firmly lock the gripper assembly in the position of Fig. 2. This operation is, of course, repeated at the opposite end of the tie rod, and at other locations where tie rods are to be arranged in the assembly of the formed panels.

Thereupon the mass of concrete, designated by the letter C, is poured and allowed to set. The resultant arrangement is seen in Fig. 2 wherein the concrete mass completely surrounds the enlarged head 30 and the base of the conical jaws 44, 46. In this connection, it is observed that the base of the conical jaws 44, 46 defines an end closure for the larger diameter end of the conical seat 32 and completely precludes leakage of concrete into the interior of the housing 12. Further, the outwardly projecting part of the enlarged head 30 defines a cylindrical depression 0' in the adjacent face of the concrete wall, which is concentric with respect to the tie rod T imbedded therein. The tie rod head or end 1." terminates inwardly of the outermost face of this depression, and accordingly, upon removal of the panels A and B with the gripper and clamping assembly supported thereon, it is possible to completely enclose the tie rod by merely patching up and covering the depression 0'.

Removal of the panels and the clamping and gripping assembly 10 from the position of Fig. 2 is accomplished by swinging the wedge from the locked position L of Fig. 5 to the-unlocked position U, illustrated by the broken lines of Fig. 5. This operation permits the panels to be grasped and pulled backwardly from the concrete mass C, to the position illustrated in Fig. 1. As the enlarged head 30 is displaced from within the cylindrical depression 0' defined thereby, clearance space is provided for i the conical coacting jaws 44, 46'which then return to the position illustrated in Fig. 1. In this position, the jaws are sufficiently spread to provide adequate clearance about the enlarged head t of the tie rod T to allow complete removal of the panels.

In the event that the jaws 44, 46 jam in the closed position of Fig. 2, the wedge 60 can be completely removed from the supported position on the end of the operator 34 by swinging the wedge 60 in a clockwise direction from the unlocked position U, illustrated in Fig. 5 by the broken lines, and displacing the bearing seat 42 upwardly along the guideway 65 until the wedge is freed. Usually it will be desirable to make the lock finger 66 of springy material and bend it inwardly to constrict the open end of the guideway, however, allowing for the finger to be urged outwardly to effect ready removal of the Wedge 60 from its assembled or supported position on the gripper assembly 32. Once thee wedge 60 is removed, nothing interferes with the complete removal of the panel with the housing 12 afiixed thereto from about the gripper assembly 32. The gripper assembly then may be inspected for the purpose of detecting the reason for jamming. However, it is to be expressly understood that the gripper assembly is sufiicie'ntly resilient to normally assume the position of Fig. 1 whenever not urged into the position of Fig. 2 due to coaction between the conical surfaces of the coacting jaws 44', 4'6 and the tapering internal bearing seat 32.

While in accordance With the provisions of the statutes, I have illustrated and described the best form of embodiment of my invention known to me, it will be apparent to those skilled in the art that many changes may be made in the form of the apparatus disclosed Without departing from the spirit of the invention as set forth in the appended claims, and that in certain instances some features of my invention may be used to advantage without a corresponding use of other features.

What I claim is:

l. A gripper for securing a tie rod to a form wall comprising an open-ended housing adapted to be fixed transversely of and extending through said wall, a pair of coacting jaws mounted within said open-ended housing for longitudinal displacement from a tie-rod receiving position wherein said coacting jaws project outwardly of one open end of said housing to a tie-rod gripping position wherein said coacting jaws are nested within and constrict said one open end of said housing, and manually operable means for displacing said coacting jaws from said receiving position to said gripping position.

2. A clamp for securing a tie rod to a form wall comprising a housing adapted to be fixed transversely of and extending substantially through said wall, a gripper assembly including a U-shaped operating member and a pair of coacting jaws mounted on the free ends of said operating member, said gripper assembly being displaceable within said housing from a tie-rod receiving position wherein said coacting jaws project outwardly of an end of said housing to a tie-rod gripping position wherein said coacting jaws are nested within and constrict said one end of said housing, and wedge means operatively connected to said operating member for displacing said coacting jaws from said receiving position to said gripping position.

3. A gripper for securing a tie rod having an enlarged end to a form wall comprising an open-ended housing adapted to be fixed transversely of and extending through said wall, a pair of coacting jaws mounted within said open-ended housing for longitudinal displacement from a tie-rod receiving position wherein said coacting jaws project outwardly of one open end of said housing to a tie-rod gripping position wherein said coacting jaws are nested within and constrict said one open end of said housing, said coacting jaws being formed with cutouts cooperating in said gripping position to define a bearing seat substantially complementary to said enlarged end, and manually operable means for displacing said coacting jaws from said receiving position to said gripping position.

4. A gripper for securing a tie rod to a form wall comprising an open-ended housing adapted to be fixed transversely of and extending through said wall, a pair of coacting jaws mounted within said open-ended housing for displacement from a tie-rod receiving position wherein said coacting jaws are spaced apart and project outwardly of one open end of said housing to a tie-rod gripping position wherein said coacting jaws abut against each other and are nested within and constrict said one open end of said housing, cooperating means on said coacting jaws and said housing for urging said coacting jaws into abutment in response to movement from said receiving position to said gripping position, and manually operable means for moving said coacting jaws from said receiving position to said gripping position.

5. A clamp arrangement for securing a tie rod having enlarged ends to a form wall having inner and outer faces comprising an elongated open-end housing adapted to be fixed transversely of said wall with one open end projecting outwardly from said inner face and with the other open end substantially coplanar with said outer face, gripping means mounted in said housing for longitudinal displacement between extended and retracted p0 sitions relative to said oneopen end, said gripping means including a common resilient operator having a pair of adjacent supporting ends and jaws on said supporting ends spaced apart in said extended position for the re'- ception of an enlarged end of said tie rod, and cooperating means on said housing and said gripping means for urging said jaws toward each other in response to supporting ends and jaws 'on said supporting ends spaced apart in said extended position for the reception of an enlarged end of said tie rod, and cooperating means on said housing and said gripping, means for urging said jaws toward eachother in response to movement into said retracted position, the outwardly projecting part of said housing being enlarged to provide a clearance space permitting return of said gripping means to said extended position.

7. A clamp arrangement for securing a tie rod having enlarged ends to a form wall having inner and outer faces comprising an elongated open-end housing adapted to be fixed transversely of said wall with one open end extending outwardly of said inner face and with the other open end substantially coplanar with said outer face, gripping means mounted in said housing for longitudinal displacement between extended and retracted positions relative to said one open end of said housing, said gripping means including a resilient U -shaped operator and jaws on the free ends thereof, said jaws being spaced apart in said extended position for the reception of an enlarged end of said tie rod, cooperating means on said housing and said gripping means for urging said jaws toward each other in response to movement into said retracted position, and a wedge adapted to bear against said outer wall and removably connected to the curved end of said U-shaped operator for longitudinally displacing said gripping means from said extended position to said retracted position.

8. A clamp arrangement for securing a tie rod having enlarged ends to a form wall having inner and outer faces comprising an elongated open-end housing adapted to be fixed transversely of said wall with one open end projecting outwardly from said inner face, gripping means mounted in said housing for longitudinal displacement between extended and retracted positions relative to said one open end of said housing, said gripping means including a resilient U-shaped operator having free ends and a curved connecting bight and jaws on said free ends, said jaws being spaced apart in said extended position for the reception of an enlarged end of said tie rod, internal camming surfaces on said housing engaging said jaws for urging said jaws toward each other in response to movement into said retracted position, and a wedge removably and swingably mounted on said curved bight of said U-shaped operator for longitudinally displacing said gripping means from said extended position to said retracted position.

9. In combination with a concrete form wall having inner and outer faces, a clamp for securing a tie rod having an enlarged end to said form Wall, said clamp including an elongaged open-ended housing fixed transversely of said form wall and extending between said inner and outer faces, gripping means mounted in said housing for longitudinal displacement between extended and retracted positions relative to said inner wall, said gripping means including jaws arranged to be spaced apart in said extended position for reception therebetween of said enlarged end of said tie rod, said jaws being dimensioned to close the open end of said housing adja cent said inner wall in said retracted position, said jaws being formed to embracingly engage said enlarged end of said tie rod in said retracted position.

10. A clamp arrangement for securing a tie rod having an enlarged end to a concrete form wall having inner and outer faces comprising an elongated open-end housing adapted to be fixed transversely of said wall and having a projecting part arranged outwardly of said inner face, gripping means mounted in said housing for longitudinal displacement between extended and retracted positions relative to said projecting part, said gripping means including a pair of jaws arranged in spaced apart relation in said extended position for the reception of said enlarged end of i said tie rod, and cooperating means on said housing and said gripping means for urging said jaws toward each other in response to movement of said gripping means into said retracted position, said part of said housing being enlarged to provide a clearance space in a formed concrete wall permitting return of said pair of jaws into spaced apart relation when said form wall is displaced relative to the formed concrete wall.

11. A clamp arrangement for securing a tie rod having an enlarged end to a form wall having inner and outer faces comprising an elongated open-end housing adapted to be fixed transversely of said wall with one open end adjacent said inner face and with the other open end substantially coplanar with said outer face, gripping means including jaws mounted in said housing for longitudinal displacement between extended and retracted positions relative to said one open end, said jaws being spaced apart in said extended position for the reception of said enlarged end of said tie rod, cooperating means on said housing and said gripping means for urging said jaws toward each other in response to movement of said gripping means into said retracted position, and a wedge adapted to bear against said outer wall and connected to said gripping means for longitudinally displacing said gripping means between said extended and retracted positions.

12. A clamp arrangement for securing a tie rod having enlarged ends to a form wall having inner and outer faces comprising an elongated open-end housing adapted to be fixed transversely of said wall and with one open end adjacent said inner face, gripping means mounted in said housing for longitudinal displacement between extended and retracted positions relative to said one open end, said gripping means including jaws arranged to be spaced apart in said extended position for the reception of an enlarged end of said tie rod, internal camming surfaces on said housing engaging follower surfaces on said jaws for urging said jaws toward each other in response to movement of said gripping means into said retracted position, and a wedge operatively connected to said gripping means for longitudinally displacing said gripping means between said extended and retracted positions.

References Cited in the file of this patent UNITED STATES PATENTS 2,173,698 Schenk Sept. 19, 1939 2,395,204 Symons Feb. 19, 1946 

